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Appeared on: Wednesday, May 30, 2001
1.3GB Fujitsu Magneto-Optical MCE 3130 AP and SS


1. Introduction

Introduction

There is no doubt, a remarkable progress in data storage related technologies throughout the last 2 decades has opened new ways for excited developments on every aspect of today?s computing systems. The constant need for more and more free available storage space is accompanied by the need of users to be able to transfer their data from system to system, in locations where transfer by ?wire? over existing networks is uneconomical or even not feasible at all. Moreover, all those multimedia files plumbing our hard disks are desperately seeking their way to a safe backup place.

Two similar and in some respects complimentary technologies come to support us (regular users) into solving these data transfer and backup problems. They offer us optical recording devices with the accompanied media in the form of a 12cm CD, CD-R, CD-RW, and DVD disks, and magneto-optical drives making use of media sealed into 3.5?, floppy-factor, cases.

Fujitsu is a leading supplier of magneto-optical drives. Two of these drives are the MCE 3130 AP/SS (the first based on an ATAPI/IDE interface, the second on a SCSI), capable of reading and writing to 3.5?, 1.3 Gigabytes removable disks as well as to older smaller capacity disk types. The 1.3GB capacity disks (and the forthcoming 2.6 GB ones) might be considered as direct antagonists to the latest Double Density CD format by Sony and the Multilevel (ML) CD?s soon to be offered by Plextor and other manufacturers. Offering similar storage characteristics as these other new formats, the magneto-optical drives by Fujitsu promise to deliver three distinct advantages, each of which is known to break existing technology shortcomings by which suffer pure optical recording drives:
  1. Short media access times, approaching those of fixed disks.
  2. Very large numbers of repeated media erasure and re-recordability. In fact, the reusability of the magneto-optical disks far exceeds that of even the DVD-RAM and DVD+RW formats.
  3. Smaller media cases. Actually the disk area of these disks is about on fourth of of the competing optical disks.

We provide some complimentary material, along with a critical approach to the relevant technologies at an Appendices of this review. For now we will strive to justify all of the above claims (at least those feasible for a publication aiming to end-user attention).

We start by presenting in the following section a brief review of magneto-optical technology. We will then focus on particular characteristics of the MCE-3130-AT/SS drives and we will carry out a series of tests for assessing their performance. We hope the reader will find rewarding our effort.


2. An outline of Magneto-optical technology

An outline of Magneto-optical technology

Let us first understand how writing and reading takes place on a magneto-optical medium. (The various graphs we will use below for illustration purposes are due to Fujitsu, Konica and other manufacturers of the magneto-optical alliance).

Write/erase cycle

Inside a 3.5? case, the MO disk consists of a series of layers, each one of them offering support to distinct aspects of the implementation of the respective technology.

First, a ?high? power laser-beam raises the temperature of a particular point at the active layer on a MO medium. When at the same time BIAS magnetic field is applied perpendicularly to the medium, the local temperature of the particles at the region of this point goes up to the "Curie point (180-200 ░C). Then, the direction of magnetization on this particular point becomes reverse (angle change). After the laser beam is switched off, the magneto-optical layer cools down very rapidly. The information is then fixed on the medium and it can be altered only by using a laser beam and a BIAS magnet again. The data is more securely stored compared to conventional magnetic disks, on which even a small magnet can cause loss of data.

The operation of erasure follows the same principles as above.

Direct overwrite technology (DOW)

With conventional MO recording technology, 3 rotations (erasing, writing and verification) are necessary to write data onto a disk. A new MO recording technique, called Laser Intensify Modulation - Direct Overwrite (LIM-DOW), enables the erasing and writing functions to occur simultaneously; i.e., the writing operation can be performed by only one rotation (direct overwrite).

Taking into account that due to current limitations of the new technique the rotation speed of the disk is forced to be lower during writing, the LIM-DOW technology delivers just 1.5 times faster writing performance than traditional writing methods (instead of a 3-fold speed increase as expected). This technology requires that the laser and the other drive electronics that control the functioning of the beam to be able to modulate at 3 distinct levels. Additionally, new media should be formulated containing 6 different layers. These layers consist of different material mixtures as follows: Read out layer (GdFeCo), Memory layer (TbFeCo), Intermediate layer (GdFeCo), Writing layer (DyFeCo), Switching layer (TbFeCo), and Initializing layer (TbFeCo).

The reading operation

When reading data on the MO disk, the application of an external magnetic field is not required. The entire reading operation is processed optically. A laser beam with less energy than that used for the writing process is projected to the MO disk to detect the points that where polarized during writing. Then, the polarized angles are converted to electric signals. Demodulation and error correction is then applied to deliver the 1?s and 0?s of the originally written information on the disk.

The MSR Technology

To achieve more than 1GB of written data onto a single disk, a new optical detecting scheme has been developed by Sony and Fujitsu called MSR (Magnetically induced Super Resolution) technology. The MSR technology enables doubling of track-density and recording-density while being able to keep full compatibility with respect to the original ISO Standards for Magneto-Optical recording.

GIGAMO™ is the name of the new standard for the case of 3.5-inch magneto-optical disks. It can achieve capacities of 1.3GB per disk, or more (2.6 are on the horizon and 5.2 and 9.1GB are promised to follow). Please note that GIGAMO is not the name of any particular MO product.

The GIGAMO standard specification is based on media of identical physical dimensions with earlier MO disk formats. Both disk drives and cartridge cases based on the current ISO/IEC standards are fully utilizable on drives based on the new technology. As a matter of the MO alliance manufacturers? decision it thus retains full compatibility with all existing media. In many cases existing disk writing/reading speed performance increases. This will be exhibited in the following test sections.

GIGAMO was jointly developed by Sony and Fujitsu, with Sony taking responsibility for the media and Fujitsu for the disk drive development.

Major drive manufacturers such as Olympus and Konica, and media makers like Kyocera, Teijin, Toso, Hitachi- Maxell, Mitsubishi Chemical, Phillips/PDO, and recently Ritek (the largest Chinese optical/magneto-optical media manufacturer in Taiwan mainland) have all agreed to support the new GIGAMO standard.

The reader can find more details on MSR technology in Appendix II of this review.


3. Specifications and installation of the tested drives

Specifications and installation of the tested drives

The specifications of the two drives of our review, as provided by the manufacturer itself, are as follows:

MCE 3130 AP MCE 3130 SS
1.3GB internal drive with ATAPI interface 1.3GB Ultra-SCSI internal MO drive
Fast internal data transfer rate: up to 5.9MB/s. Fastest internal data transfer rate: up to 6.7MB/s
High rotational speed: 3,214 rpm / 4,558 rpm* Highest rotational speed:
Normal mode: 3,637 rpm (1.3GB disk) / 5,455 rpm (other disks)
ZLCV mode*: 3,637 - 4,801 rpm (1.3GB disk) 
Excellent random accessibility: 23 ms seek time Fastest seek time: 19 ms
Full read/write compatibility with 1.3GB GIGAMO disks and all ISO 3.5" MO disks (640MB, 540MB, 230MB and 128MB) Full read/write compatibility with 1.3GB GIGAMO disk and all ISO 3.5" MO disks (640MB, 540MB, 230MB and 128MB)
*MCE3130AP has two rotational speed modes with 3,214 rpm for a 1.3GB disk and 4,558 rpm for other lower capacity disks. *MCK3130SS automatically activates ZCLV mode for sequential multimedia files and controls the rotational speed ranging from 3,637 rpm up to 4,801 rpm using 1.3GB disks. 

In the following section we will perform a series of exhaustive tests to find out whether these claims stand on their own or not.

Other 1.3GB drives by Fujitsu

The following drives use the same basic mechanism, but utilize a different interface:

All three drives appear on the market today at a higher price than the standard ATAPI drive we tested. (It seems the Fujitsu marketing department does not consider they fulfill basic end-users' needs...)

Installation

In the front cover of both drives there is the GIGAMO logo. The ATAPI model has the MO 1.3GB logo on the right of the tray as well. On the front panel there is an eject button and an emergency eject hole (as expected).

Since both drives aim to be compatible with a wide platform hardware, there are ample jumpers at the rear end of both. The following guide instructs the user on the switch and jumper settings in the MCEMCE3130SS model during installation. The factory default settings are marked with an asterisk.

The following SW1 (Switch 1) sets the SCSI ID and some other drive functions.

CHN1 (external switch setting) sets the power and SCSI termination. It uses shorting bars to set the power source and to enable or disable SCSI termination.

The CNH2 (external switch setting) sets additional drive functions.

Most current OS?s have build-in support for MO devices. There might be some problems with Win95 or WinNT (earlier than version 4.0), so Fujitsu suggests using their installation drivers package. The drivers also install a .VXD driver in order to increase the reading/writing performance of both IDE/SCSI models on these operating systems. So any user still using these OS's is advised to install them.

To install the drives we used the version 5.01E software package provided at the Fujitsu?s Japanese site. After installation, Windows Me correctly recognized the drives as Fujitsu MCE3130AP and MCE3130SS respectively.

Fujitsu suggests not to enter any disk in the drive, before you turn if on. Upon its first power on, the drive will make a ?click? sound and afterwards you can use it without any problems.

Of course, MO optical drives work only with formatted media. Fujitsu provides the ?MO Disk Formatter? utility, a media formatting software. This software is not needed under Windows 2000 or later. Right-clicking on the MO drive?s icon under Windows Explorer the option of formatting the disk is offered. (Please take note that if you decide to perform a low-level format, such as in the case where the disk has been damaged or severely overused, you will need to use the supplied software even under Windows 2000!)

Let?s have a look at this software.

First, select the MO drive. (If there is no MO disk in the drive, the message ?No disk in the drive? is displayed.) The MO disk formatter supports both floppy and hard disk type formats (FAT 16/FAT 32) so that it can be used as a large capacity floppy disk. This format can be used on almost all machine types and operating systems. (The FAT 32 format type can make use of a greater number of clusters than FAT 16, using a smaller cluster size. It is supported on Windows 95 OSR 2 or later operating systems by Microsoft.)

This program cannot set multiple partitions on a single disk. It seems this is a restriction of the drivers and is probably due to a lack of interest in part of the manufacturers to define such a layered logical format for the MO disks.

The user is also offered the option of performing a low level disk format. This type of format scans the entire MO disk in order to optimize its performance and takes 15 to 20 minutes (for the 1.3GB disk). Low level formatting is recommended for older, heavily used MO disks. (Note that low level formatting cannot be canceled once it is started.)

The program also indicates the sector size and the capacity of the MO disk inserted. Theá sector size in this screen is the number of bytes per sector. While the ?raw? sector size is always 1 kilobyte long, the logical sector size can be defined on this screen of the program.

It can be set to 4 or 2Kbytes in the options tab. This function is allowed when Floppy Type (FAT 32) or Hard Disk Type (FAT 32) is selected and only when the disk size is 540MB or greater. As said above, FAT 32 Formatted MO disk can save the data more efficiently. (However, an operating system that supports FAT 32 is required to use FAT 32 formatted disks.) You can also set a name to the disk in the "Volume Label" textbox, which can contain up to 11 characters with alphanumeric characters and the _ symbol (underscore).


4. Performance tests

Performance tests

We assessed the writing and reading performance of the MCE3130SS Ultra-SCSI and MCE3130AP ATAPI MO drives using SCSI Mechanic v.3.0 as the testing software. We tested both drives with MO disks of varying capacities supplied to us by Fujitsu. The disk capacities were 1.3GB, 640MB, and 540 MB. We also tested the drives using 230MB disks manufactured by Verbatim. For all our tests we formatted the disks under HD-FAT32. The DMA option was enabled for the IDE model during our tests and also Sync Data Transfer option was set on for the SCSI model tests.

Test machine

The results are shown in the chart below.

SCSI MECHANIC RESULTS

  Media Read Media Write
MO Drive Disk
Capacity
Random Sequential Butterfly Random Sequential Butterfly
MCE
3130 AP
1.3GB 1722

3504

1085

837

933

580

640MB 1285

3108

974

750

1320

666

540MB 1256

2593

925

565

800

468

230MB 853

1615

735

501

640

326

MCE
3130 SS
1.3GB 1732

3496

2193

611

1330

1331

640MB 1308

3103

2158

775

1660

3103

540MB

1252

2600

1963

560

1820

1300

230MB

852

1521

1530

375

2630

920

The following charts provide a visual presentation of the above data and present a reading and writing performance comparison among theá various MO media. All disks were tested in random, sequential and butterfly mode access modes.

In the random access test, MC 3130AP manages to reach a 1722 Kb/sec transfer rate while reading from the Fujitsu 1.3GB MO disk. Rates seem to be lower when the drive reads from 640MB or lower capacity disks. It seems that LIM-DOW technology has not matured yet. The simultaneous use of both land and groove bits forces the drive to spin at a lower speed!

The sequential reading performance climbs to 3504kb/s for the 1.3GB disk and becomes lower as the tested media are of lower capacities. The same reading behavior appears also in the butterfly reading tests, where the transfer rates start from a 1085kb/sec (1.3GB) transfer rate to gradually come down at a 735kb/s rate for the 230MB disk. It seems as the rate difference in this case diminishes. Older (and thus lower capacity) disk formats compete more efficiently with newer (and presumably) more efficient disks. This is normal, however, as this type of test exercises heavily the pickup head in seek time loads. As this time decreases only marginally at the newer formats, this behavior is normal.

In the random writing performance tests, MC 3130AP gave an 837 kb/sec transfer rate when used with 1.3GB MO disks. Sequential writing test gave an unexpected result for the 640MB disk. The 1320 kb/sec transfer rate is the best among the other media performances, including the 1.3GB disk. The same applies to the butterfly tests as well. This obviously reveals a better compatibility of MC 3130AP with 640MB media in writing sessions, and is due to limitations of the current drive series in dealing with media recorded both in land and grooves. We expect this to change when newer drives compatible with the 1.3GB medium will be introduced.

As you can see in the chart on the left, the MC 3130SS model has the same transfer rate performance as the ATAPI model in the random and sequential tests. The results are better in the butterfly tests, where the transfer rates are much higher than those offered by the ATAPI model.

In the random writing tests, the 640 MB disk offered the best performance (775kb/sec) among the other media tested. The sequential writing results place the 230MB disk in the first position with a 2630 kb/sec transfer rate. The 540 MB disk is in the second place, giving a 1820kb/sec rate. The 640 MB disk performed better in the butterfly test, where it gave the highest result (2103kb/sec). The 1.3GB and 540BM media gave the same transfer rates, approximately 1300kb/sec and finally, the Verbatim 230MB disk performance, reached only 920kb/sec.

Considering the test results above, we could say that the Fujitsu MC 3130AP (ATAPI) and MC 3130SS (SCSI) models behave almost the same when reading the various MO media. The main performing differences come in the writing sessions, where the SCSI model seems to give higher transfer rates. This is certainly not due to any BUS superiority, as this would apply in the reading case as well. We may thus safely assume that it is due to a firmware restriction. Probably the SCSI models are based on a higher quality lasers! (Might it be the case that during production the best apparatus is probably used on the SCSI models, and those passing the quality tests next are used for the ATAPI models?)

We also tested the access times of the drives using same media capacities as previously. The software that was used in this case was the Ziff Davis ?Media?s WinBench 99 v.1.2?. The ATAPI model gave the same access time results as the SCSI drive. The best performance (36.1 msec) comes from the lower capacity disk (230MB). The drive accessed the 540MB and 640MB disks at an average of 37 milliseconds throughout the media?s surface. The highest access time was given when the tested media had a capacity of 1.3GB.


5. Conclusion

Conclusion

Fujitsu Magneto-optical (MO) drives seem to be an attractive proposal for the user who needs an alternative, to the plain old compact disk, removable storage medium format.

Serving multiple functionalities, the Fujitsu MO drives can be used as a secondary Hard Disk (1.3GB) of a lower however capacity, a descent backup solution for moderately sized user data, or a high capacity floppy disc for everyday office-to-home file transfers. With installation and usage simplicity, even novice users who are asking for an economical and reliable solution can easily adopt MO drives. Buffer underruns and drive-to-media incompatibilities from which frequently suffer other formats, such as the compact disks, are unknown to MO drives and media.

On the other hand, with cartridges that are impervious to dust, moisture, and shock, Fujitsu MO disks are extremely rugged and highly tolerant of the problems that plague regular magnetic media.

It is important to take into account when making your own assessment that each MO disk comes with a lifetime warranty.

The power point of Fujitsu MO drives is the low random access times. Officially Fujitsu claims that MO drives can randomly access a MO disk at an average of 23msec. Our tests showed a access times in the area of 35msec. As for the transfer rates achieved, they are lower than those an optical CD-R drive can give today.

However, the MO technology will not disappoint the candidate MC 3130AP or MC 3130SS buyer. Fujitsu is already developing the 2.3GB MO line of drives, while it has promised the even larger capacities of 5.2 and 9.1GB per disk.


The reader might also read the appendices to this review by clicking the relevant links below and to the right.


6. Appendix I. Fixed Storage versus Removable storage

The evolution of optical data storage technologies

Today?s hard disk devices support gigantic capacities, allowing the storage of large amounts of data with high availability and safety. When we talk about storage, we usually have in mind the hard disk drives. Fixed hard disk drives offer almost everything a home or office user needs. All except an easy method of transferring data between different computer systems. Furthermore, they are not immune to magnetic field radiation and by no means can they be considered a permanent storage solution. The read signal deteriorates in a few year?s period.

But what about our everyday desktop needs for removable, reliable and economical storage? The (not too much) unexpected explosion in CD recordable/rewritable drives sales over the period of the last few years, have prompted optical media into a leading position in the removable data storage category. Optical and magneto-optical drives now offer the same alternative solutions once offered by the floppy discs, now an area occupied by Compact Disk.

Removable media technology is currently lagging fixed-storage achievements in both raw performance and price cost per available disk space offered. For example, compare the 40MB hard disks embodying the early 1990?s PCs with the 15GB per disk standard capacity of a typical system today. A 30-fold increase in available storage, with a marginal decrease in cost!

In contrast, a DVD-ROM drive typically equipping a modern PC, offers just an 8-fold available disk space increase, at about the same amount of money.

In the case of MO media technology, and during the same as before time-frame, we went from a 3.5", 128MB disk available to consumers during the first MO device shipments of Fujitsu in early 90?s, to 1.3GB disks capable drives today. Roughly the same overall capacity increase as in the case of the more commonly available optical disks.

The Fujitsu proposition

Fujitsu, Japan, is the leading manufacturer of a series of magneto-optical. Starting from the original 128MB magneto-optical (MO) media in early 90?s, it now offers modern drives capable of reading/writing media of an 1.3GB capacity, with a soon to be released 2.6GB capable drive, all the way up to a promised drive that will be able to use 9.1GB media!

 

However, the bigger the capacity of a removable disk and the greater its price cost is, the more it grows the user?s concern on its reliability. Fujitsu has an alternative solution for removable storage: The MCE3130 Magneto-Optical (MO) internal drive series.

According to Fujitsu, a magneto-optical disk drive, is a computer data storage device covering the most of the features and properties wanted and needed by desktop computer users. It can store large amounts of digital data - digital still photos, video clips, Internet downloads, and of course any size text files - easily, quickly and securely.

As can be seen in the side picture, the MO disk, the heart of the system, is almost the same size as a standard floppy disk. The available media capacities are 128MB, 230MB, 540B, 650MB and 1,3GB made by Fujitsu, Maxell, PDO Media, Sony, Teijin and Verbatim. A MO disk can easily store 850 times more data than a conventional 1.44MB floppy, that's 1.3GB of information in one MO disk. The 1.3GB media are based on GIGAMO, which, as explained in an earlier section, is a new 3.5-inch magneto-optical technology standard, featuring the Magnetically induced Super Resolution (MSR) technology.


7. Appendix II. MSR technology details

Appendix II. MSR technology details

The following picture shows the exactly how the magnetic mask mechanism is implemented on the various media layers.

The Reading and Middle layer have different temperature distributions (from low to high) relative to the elapsed time, as the laser beam, due to the disk rotation, comes over a particular bit of the disk and is irradiated.

In the part of the disk where the temperature is low, the magnetization of the particles in the middle layer is directed in parallel to the externally applied field. Subsequently, the particles in the reading layer are set to the same orientation regardless of the orientation of the recording layer. Thus a front mask is created as shown at black spot on the side picture.

In the part of the disk where temperature is high, because of the fact that the particles in the middle layer have been heated at a temperature higher that that of Curie point, the magnetization is lost. Consequently, at of the reading layer each particle is magnetized in the direction of the applied magnetic field. This creates a rear mask, the white spot in the picture.

Only a part of the disk in the middle layer characterizes the direction at which the recording layers are magnetized. This allows an easy distinction of the polarization of the data bits and easily enables the drives electronics to recover the recorded data.

The gain of recording density is clearly shown in the picture below, where you can see the read out (analog) signal differences between MSR and normal MO reading.

In short, MSR Technology aims to reduce the interference among neighboring recorded bits (intersymbol interference). Magnetic interference is a phenomenon by which suffer not only MO but pure magnetic media as well. In our case it emerges when reading fromá two or more consecutive polarized spots (bits). Intersymbol interference limits the attainable recording density. As it can be seen in the relative graph, MSR encloses each spot in a magnetic mask creating an appropriate magnetic isolation which enables an easier detection of the relative peaks in the analog waveform readout. According to Fujitsu, the application of the MSR technology can increase the recording density by 2 to 4 times.


The table below lists major characteristic values of the relevant specifications for each MO media type.

  Disk Capacities
 

128MB

230MB

540MB

640MB

Track pitch [micro-m]

1.60

1.39

1.10

1.10

Modulation

RLL2-7

RLL2-7

RLL1-7

RLL1-7

Sector length [bytes/sector]

512

512

512

2048

Linear density [micro-m/byte]

8.7 to 13.7

7.1

4.0

4.0

Bit transfer rate [M Bit/Sec]

21.8

26.1 to 41.8

35.0 to 58.8

34.9 to 58.1

Maximum frequency of data

7.25MHz

13.92MHz

14.71MHz

14.54MHz

From the above table we can see that while since mid 90's all hard disks employ PRML (partial response, maximum likelihood) encoding schemes, all MO drives (up to those tested here) employ pure peak detection (RLL).

The newer 2.6GB, 5.2GB and 9.1GB disk formats will be encoded under a PRML scheme. Perhaps part of the reason that these larger capacity disks will be attainable might be the employment of this newer encoding technology.

Unfortunately, unlike the CD and DVD format cases, where there is abundance of available technical information to the public, in the case of MO recording we were unable to obtain the necessary technical information. It seems that the MO disk alliance wants it to be this way:)


8. Appendix III. Mini FAQ for MO drives

Appendix III. Mini FAQ for MO drives

The following is based to a large extend on information provided by the relevant drive and disk manufacturers. It is included here purely for user convenience.

1. Why do MOs have a high resistance to dirt and scratches?

Data is written to and read from the recording layer of an MO disk through a thick polycarbonate substrate. The diameter of the laser beam is wide at the point where it strikes the disk surface, but becomes narrower towards the recording layer. Therefore, dust and scratches on the disk surface hardly affect the generated signals.

Even if the disk surface has a large piece of dust or a deep scratch that is likely to affect the signals, the employed"powerful" error correction scheme can reproduce the original signals correctly. Since the optical pickup DOS not come in contact with the disk and is separated from its surface by approximately 1mm, there is almost no chance that the disk surface will get scratched due to dust.

Moreover, remember that as in the case of DVD-RAM disks the disk is sealed into a case. Our experience suggests that 95% of all disk reading problems from disks that originally had no defects, comes from incorrect handling in part of the user!

2. Why are MOs unaffected by magnetic fields?

The recording layer of an MO disk is made by TbFeCo, a material that has extremely high coercivity. The MO drive projects a laser beam to heat up the magnetic substance to a temperature at which it loses its magnetism, and then starts writing data. MO disks can still record in the presence of weak magnetic fields, but not at normal room temperatures. Therefore, bringing a conventional magnet close to an MO disk at room temperature will not corrupt the data on the disk.

Possible MO operation problems

3. Scan Disk takes an extremely long time, and I had to cancel the operation. What do I do?

There is a possibility that physical or logical format information was corrupted when the formatting operation was interrupted. If the disk is in a state in which it can be formatted physically, use the formatter that came with your device driver to format the disk physically, then reformat it in MS-DOS format, and you should be able to use the disk again. Remember that if you format a disk, any data on it will be destroyed.

On Windows 95, an unformatted disk cannot be "quick formatted." Use "normal formatting."

4. I inserted a disk into the drive, but it is not recognized

Data on the disk is unreadable. Check that your disk is formatted. Alternatively, logical format information may be corrupted. Use commercial repair software to find out how severe the damage is, and repair it, accordingly.

Dirt on the disk or lens sometimes prevents the disk from being recognized.

5. Data cannot be written. Running ScanDisk or Norton utilities results in a "Defective clusters generated" message. What do I do?

First, make sure that the disk is not write-protected. The drive may not have enough recording power (due to dirt on the lens, laser deterioration, etc.) or the disk may be dirty.

6. Why can't 540 MB and 640 MB disks be used?

Check the manual of your drive and see if it is compatible with 540 MB or 640 MB disks. (If your disk is for 128 MB/230 MB size disks, 540 MB or 640 MB disks cannot be used.)

On a 640 MB disk, one sector holds 2,048 bytes. On 540 MB, 230 MB and 128 MB disks, one sector contains 512 bytes. To use a 640 MB disk on Windows 3.1 or MS-DOS, you need the proper device driver for 640 MB disks. Check with your dealer.

7. Why does my disk drive misidentify the inserted disk and hang up when I exchange a 128 MB/230 MB/540 MB disk with a 640 MB disk?

Exchanging a 128 MB/230 MB/540 MB disk (512 bytes per sector) with a 640 MB disk (2,048 bytes per sector) may sometimes cause this problem. Restart your computer before inserting a disk with a different sector size.

8. After I attempted to copy a file, I received a message saying "Too many files exist," and could not copy the file although there was enough free space. Why?

If an MO disk is formatted in Super-Floppy format, only 512 folders or files can be stored under the root directory. If you attempt to create any more folders or files, you receive this error message. Delete any unneeded files and create a new folder, then copy the new file to the folder. Drive supplier provides a device driver to avoid this problem. Install the device driver before you use a MO drive.

9. A DOS/V formatted disk cannot be accessed on Windows NT 4.0. Why?

Because Windows NT 4.0 has its own format, certain types of disks cannot be accessed. Use the disk administrator to allocate the areas and reformat the disk.

10. Disks used on Windows 95, Windows NT 3.1 or Windows 3.1 cannot be read on Windows NT 4.0. Why?

As described above, certain types of disks may be unreadable due to differences in format, even if the device drivers you are using can support these disks.

11. What are the advantages over competing formats? (ZIP)

12. Advantages over CD-R/RW

10. Disadvantages over competing formats

To be completed based on actual user feedback we will receive:)

 



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